Surface cleaning apparatus

ABSTRACT

A cleaning machine that includes a drive unit and a trailer unit joined by an articulated joint, the drive unit including a pick up assembly having a reversible power driven paddle wheel mounted in a housing to extend closely adjacent the surface to be cleaned, the housing including leaf flap mechanism mounted for movement between a downwardly extending position and an elevated position, a duct mounted on the drive unit frame and having an inlet for receiving raised material from the housing, an airstream outlet, and at a lower elevation than the airstream outlet, a heavy debris outlet opening to a heavy trash receptacle on the frame, the heavy trash receptacle having doors for discharging the heavy trash, a suction blower having an inlet fluidly connected to the duct airstream outlet and a door for selectively blocking fluid communication between the duct and suction blower, a motor for driving the drive unit and having a directly driven shaft with a brake disc thereon, and mechanism to move the housing to an elevated transport position; and that the trailer unit includes a frame having a dump container thereon, a discharge door at the rear of the container, the container having a top filter portion, a standard on the tractor frame for stationarily mounting one end of a duct for placing the container in fluid communication with the suction blower outlet when the container is in a debris receiving position, and a deflector adjacent the container inlet for deflecting air and debris downwardly.

United States Patent [1 1 Krier et al.

[111 3,881,215 May 6,1975

[ SURFACE CLEANING APPARATUS [75] Inventors: Keith N. Krier, Hopkins;Paul W.

Kimzey, St. Louis Park, both of Minn.

[73] Assignee: Tennant Company, Minneapolis,

Minn.

[22] Filed: Dec. 19, 1972 [21] Appl. No.: 316,457

2,913,744 11/1959 Gregersen.... 15/340X 3,093,853 6/1963 Tamny 15/833,300,807 l/1967 Berkowitz 15/340 FOREIGN PATENTS OR APPLICATIONS 83,2579/1895 Germany 15/349 Primary ExaminerPeter Feldman Assistant ExaminerC.K. Moore Attorney, Agent, or Firm-Dugger, Johnson & Westman [57]ABSTRACT A cleaning machine that includes a drive unit and a trailerunit joined by an articulated joint, the drive unit including a pick upassembly having a reversible power driven paddle wheel mounted in ahousing to extend closely adjacent the surface to be cleaned, thehousing including leaf flap mechanism mounted for movement between adownwardly extending position and an elevated position, a duct mountedon the drive unit frame and having an inlet for receiving raisedmaterial from the housing, an airstream outlet, and at a lower elevationthan the airstream outlet, a heavy debris outlet opening to a heavytrash receptacle on the frame, the heavy trash receptacle having doorsfor discharging the heavy trash, a suction blower having an inletfluidly connected to the duct airstream outlet and a door forselectively blocking fluid communication between the duct and suctionblower, a motor for driving the drive unit and having a directly drivenshaft with a brake disc thereon, and mechanism to move the housing to anelevated transport position; and that the trailer unit includes a framehaving a dump container thereon, a discharge door at the rear of thecontainer, the container having a top filter portion, a standard on thetractor frame for stationarily mounting one end of a duct for placingthe container in fluid communication with the suction blower outlet whenthe container is in a debris receiving position, and a deflectoradjacent the container inlet for deflecting air and debris downwardly.

9 Claims, 8 Drawing Figures PMENTEDHAY 6l975 3.881.215 sum 10F 5 vPMENTEUHAY s 1975 SHEET 2 OF 5 PMENTEDHAY ems SHEET 3 BF 5 PATENTED um s1975 SHEET U U? 5 SURFACE CLEANING APPARATUS RELATED APPLICATIONS Partof the apparatus disclosed in this application is more broadly disclosedin the copending application of Paul W. Kimzey, Donald L. Olson, DanielA. Delmore and Keith N. Krier, Ser. No. 316,476, filed the same day asthis application and assigned to the same assignee as this application.

BACKGROUND OF THE INVENTION A surface cleaning machine having avacuumized pick up head for picking up debris and trash from streets,parking lots, parks and the like.

It is old in the prior art to provide an articulated machine having acleaning head for cleaning areas such as lawns and parking lots, see US.Pat. No. 3,406,424 to Rush. However, such machines are not suitable forpicking up relatively heavy trash; do not provide for separation of therelatively heavy picked up materials from the lighter materials and as aresult both types of trash go through the suction blower which causesundue wearing of the fan housing and impeller; have relatively high airlosses and a relatively low air velocity in housing adjacent the area ofpick up for a given fan capacity; and require high flow rates of air andconsequently relatively larger filter capacities. In order to overcomeproblems such as the above, this invention has been made.

SUMMARY OF THE INVENTION A surface cleaning machine that includes adownwardly opening pick up head having an outlet and a paddle wheelrotatably mounted therein and selectively driven in either angulardirection, a heavy trash receptacle, a light debris collection andfilter container mounted for movement to a dumping position and a ductfor separating heavier debris from lighter debris as the debris movestherethrough, said duct having an inlet fluidly connected to the headoutlet, a light particle outlet branch, and a heavy trash outlet branch,and a suction blower having an inlet fluidly connected to the lightparticle outlet branch and an outlet fluidly connected to the container.

One of the objects of this invention is to provide a new and novelsurfacing cleaning machine having a vacuumized pick up housing, and apaddle Wheel to reduce air losses, maintain a relatively high airvelocity in the areas between the paddle wheel and surface being cleanedand the paddle wheel and the housing, and pick up and throw materialupwardly into the housing, and direct heavy trash into one receptacleand light trash into a light trash container.

An additional object of this invention is to provide in a surfacecleaning machine having a pick up head, a new and novel leaf flap andpaddle wheel combination that in operating the paddle wheel in oneangular direction is especially adapted for picking up large, bulky,light materials including those in relatively large accumulations, andin the other angular direction for picking up lighter debris loads andsmall dense items such as rocks and pop bottles. In furtherance of thelast mentioned object, it is another object of this invention to providea leaf flap that may be selectively retained in an elevated positionremote from the path of rotation of the paddle wheel.

A further object of this invention is to provide a new and novel debrisdeflector duct in a surface cleaning machine for separating heavierobjects from lighter objects picked up by a vacuumized pick up head.With reference to the last mentioned object, it is another object ofthis invention to provide heavy trash receptacle having a new and noveltrash discharge arrangement. An additional object of this invention isprovide in a surface cleaning machine, a new and novel duct and heavytrash receptacle arrangement for reducing air flow rate requirements andthe amount of air to be filtered, and also for separating heavy trashfrom lighter trash.

Further it is an additional object of this invention to provide a newand novel high dump arrangement for emptying a combination lightparticle collection receptacle and filter container, and a hydraulicallyoperated discharge door assembly on the container. Another ob-.

ject of this invention is to provide in a surface cleaning machine, anew and novel combination filter-debris container having an inlet and adeflector for directing debris downwardly across the container andinitially direct the air flow path away from the filter.

A different object of this invention is to provide on a surface cleaningmachine, a new and novel ground engaging wheel driving and brakingarrangement. An additional object of this invention is to provide a newand novel surface cleaning machine having a heavy trash receptacle, asuction blower, a vacuumized pick up head and a combination filter andlight debris container arranged for good balance and weight distributionin a relatively compact machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of the apparatusof this invention;

FIG. 2 is a longitudinal, cross-sectional view generally taken along theline and in the direction of the arrow 22 of FIG. 3 of the combinationdrive and pick up unit of this invention, various portions being brokenaway to show other structure;

FIG. 3 is a front view of the apparatus of this invention, portions ofthe vehicle body being broken away to show structure rearwardly thereof;

FIG. 4 is a fragmentary right side view of the trailer unit of thisinvention with portions thereof broken away, said view showing therefuse container and container outlet door in a datum position in solidlines, the door in a dump position relative container in a datumposition in dotted lines, and part of the container in the dumpingposition in dotted lines together with the linkage for moving thecontainer to said dumping position;

FIG. 5 is a fragmentary top view of the right side of the trailer unit,portions being broken away to more clearly illustrate the linkage formoving the container to a dumping position;

FIG. 6 is a perspective view of the paddle wheel;

FIG. 7 is a fragmentary cross-sectional view of the differential drivemotor and brake for the drive unit of this invention together with aschematic showing of other drive components; and

I FIG. 8 is a fragmentary vertical view generally taken along the lineand in the direction of the arrows 88 of FIG. 4 to show the deflectorthat is rearwardly adjacent the container inlet port; and 7 Referring toFIG. I, the apparatus of this invention includes a combination pick uphead and drive unit,

generally designated 11,'having a main frame, generally designated 12 onwhich there is mounted a pair of motor driven, ground engaging wheels13. Connected to the drive unit by an articulated joint 14 is a trailerunit, generally designated 15, that mounts a pair of ground engagingwheels 17. Thus, the apparatus of this invention, includes anarticulated vehicle. Since the manner of forming the articulatedconnection and the manner of steering the vehicle may be the same asthat described in copending Application Ser. No. 255,612, filed May 22,1972, details of the construction of the articulated joint and thesteering mechanism will not be described herein.

Referring now in particular to FIGS. 2 and 3, the combination pick uphead and drive unit 11 includes a downwardly opening, pick up headhousing, generally designated H, that includes side walls 18 which havevertical lower portions, upwardly and transversely inwardly inclinedintermediate portions and vertical top portions. The housing alsoincludes a rear wall 19 and an upwardly and rearwardly inclined frontwall 20, the walls 18-20 being joined to one another to form a generallyrectangular rearward discharge opening 23. The lower terminal edge ofthe front wall 20 is at a substantially higher elevation than the lowerterminal edges of walls l8, 19; there being provided a front panel 21having its upper edge hingedly connected at 22 to the lower edge of thefront panel for movement about a transverse axis. The movement of thefront panel in a clockwise direction as viewed in FIG. 2 is limited byabutting against the front edges of the side walls 18. The side wallsdependingly mount resilient side skirts 25 while the rear wall mounts adownwardly and forwardly inclined rear skirt 24 that extends between theside wall skirts. Brackets 26 are secured to the lower edge of the frontpanel to mount a hinge member 33 that has a transverse hinge axis. Thehinge member mounts a front flap (leaf seal) 27 that includes a flapportion 27a which in its lowermost (vertical) position has a lowerterminal edge at about the same elevation as the lower terminal edge ofskirts 24 and 25, a reversely bent flap portion 27b that resistsrearwardly movement of flap portion 27a and a flap portion 270 thatsubstantially forms a fluid seal between panel 21 and flap portion 27b.Advantageously the flap portions 27a, 27b are provided with verticalslits 27d to permit one part of a flap portion moving rearwardlyrelative the other, for example, if one of the parts between adjacentslits engages large objects, the loss of vacuum is minimized as the onepart moves over the object from that which would have been lost 'if theslits were not provided.

In order to selectively pivot flap 27 about hinge 33 from the generallyvertical position of FIG. 2 to an elevated, generally forwardlyextending position, the sheath and adjustment nut portion 30b of aconventional push-pull cable assembly 30 are mounted by a bracket 28that is fixedly attached to the front panel 21, portion 30b permittingdownward movement of the cable operated rod portion 30a to a positionthe flap extends generally vertically. The rod portion is pivotallyconnected to a bracket 29 that is bolted to the hinge 33 opposite thehinge axis from the hing portion secured to panel 21. The push-pullcable may be operated to selectively move the flap 27 to its elevatedposition and retain the flap in said position, while a stop (not shown)is mounted on bracket 26 to limit the hing- Although it is preferredthat a flap 27 such as disclosed be used, it is to be understood otherflap constructions could be used. For example, a flexible laminated flapcould be used wherein the front laminate extends the furthest downwardlyand each successively rearward laminate lower edge terminates at aprogressively higher elevation so that lowermost parts of the flap canmore readily bend rearwardly than higher parts of the flap to aid innormally retaining the flap out of the path of movement of a paddlewheel 36.

In order to mount the housing H for movement between its datum positionshown in solid lines in FIG. 2 and an elevated transport position, links162 at their first ends are pivotally connected at 164 to a flange 19bsecured to the housing rear wall 19, while the second ends of the linksare pivotally connected at 163 to the lower front corner portions of theside walls 43. At a higher elevation than links 162, there are providedlinks 166 that are pivotally connected at 167 to the side walls 43 andat 168 to the flanges 19b. A stop is mounted for limiting clockwisemovement of links 166 as shown in FIG. 2. As a result of the locationsof the pivots 163, 164, 167, 168 and the lengths of the links 162, 166,the housing H is mounted for vertical transatory movement. In order tomove the housing between its positions, one end of an arm 169 ispivotally connected at 170 to the housing front wall 20 adjacent thecentral upper edge portion thereof and the opposite end is pivotallyconnected at 171 to an intermediate portion of an operator control lever172 that is operable by operator sitting on the seat 31. One end of thelever 172 is pivotally connected at 173 to the drive unit frame.Suitable latch mechanism (not shown) is provided for selectivelyretaining the lever in the housing elevated position.

A driven shaft 29 is rotatably mounted by the side walls 18 and inwardlyof the side walls, the shaft being rectangular in cross sectionperpendicular to the central axis of elongation thereof. The shaft isextended through a rectangular tubular portion 36a of the paddle wheel36 (see FIG. 6). Flap portions (spokes) 36a that are of about the sameaxial length as the paddle wheel have their one edges integrally joinedto the tubular portions 36a and their opposite edges integrally joinedto the circular cylindrical tube 36c of the paddle wheel, the flapportions 36b being substantially angularly spaced from one another. Aplurality of axially elongated, radially extending flap portions 36dhave their inner edges integrally joined to the tube. The flap portions36d are substantially angularly spaced from one another with each pairbeing diammetrically opposed. The outer edges of the diammetricallyopposed pair of flaps 36d in a horizontal position are spaced by adistance only slightly less than the horizontal spacing of the rear wallfrom the lower portion of the front panel in its datum position shown inFIG. 2 while when a pair of diammetrically opposed flaps 36d are in avertical condition, the lower edge of the lowermost flap extends toabout the same elevation as the lower terminal edges of skirts 24, 25,or to an elevation just slightly above the surface being cleaned. Thusflap portions 36d substantially form fluid seals with the housing asthey are moved through horizontal planes to reduce the quantity of airdrawn into the housing, the front panel 21 being curved to be closelyadjacent a substantial portion of the outer periphery of the path oftravel of the paddle wheel. Further skirt 24 is inclined at an angle toaid in the pick up of material when the paddle wheel is rotated in thedirection of arrow 200 and minimize the amount of air drawn into thehousing between it and the paddle wheel. The mounting member 36a, flapportions 36b, flaps 36d and cylindrical tube 36c are of substantiallythe same axial lengths.

The paddle wheel 36 is made of material sufficiently resilient that thecylindrical portion thereof may bulge radially inwardly when an object,for example a can, is moved between the housing and the cylindrical tubethat has a greater dimension than the normal spacing therebetween, andwill resiliently return to its original condition when the object hasbeen moved upwardly into the housing. This aids in moving large objectsupwardly in the housing. Advantageously there may be provided aplurality of paddle wheels 36 on each shaft 35 in edge to edge abuttingrelationship instead of a single paddle wheel extending substantiallythe transverse distance between the side walls 18. Further, if desired,the hollow space between members 36a, 36c may be filled with a flexiblefoam material.

Through the provision of the cylinder tube 36c that bisects the flaps atthe juncture of flap portions 36b, 36d, which is at a locationintermediate the axially extending terminal edges of the flap portions36d and the tubular portion 36a, the volume of air lost as the paddle isrotating is minimized. That is, the tube 360 cuts down the air loss andkeeps the air velocity moving faster in the areas between the tube 360and the ground and the housing as the paddle wheel is rotated forpicking up debris. As a result the total quantity of air drawn into thehousing for picking up debris is substantially less from that whichwould be required if tube 36c were not provided. Further the flapportions 36d in moving angularly above a horizontal plane project orfling particles engaged thereby upwardly in the housing. Additionally,the tube 36c acts as a stabilizer and strengthener for the flaps andserve to control the stiffness of the flaps. The paddle wheel may beformed by molding and may be made of rubber, neoprene, urethane or othersuitable flexible material. Since the tube is made of flexible material,the tube in rotating and engaging large objects between itself and theground will start to move the object for pick up in either angulardirection of rotation of the tube, and in rotating can flex inwardly topermit passage of objects of a greater longitudinal dimension than thenormal corresponding dimension between the tube and the adjacent part ofthe housing front and rear wall respectively, depending on the directionof rotation.

In order to drive the paddle wheel in either one angular direction or inan angular direction opposite thereto, a hydraulic motor 39 is mountedon the housing H and has a sprocket (not shown) keyed to the motor shaftthereof for driving a chain 40 which in turn drives a sprocket (notshown) keyed to the paddle wheel shaft 35. Suitable hydraulic circuitry,including a control (not shown) located adjacent the operators seat 31,is provided for operating the motor 39 in the selected angulardirection.

A duct, generally designated D, has side walls 43, and a bottom wall 44that is upwardly and rearwardly inclined at a relatively steep angle,for example over 45, and located in substantially the same plane as therear inclined portion 19a of the housing wall 19 when the housing is ina datum surface cleaning position of FIG. 2, wall 44 and wall portion19a being substantially parallel to the housing front wall 20. Theperpendicular spacing of wall portion 19a from wall 20 is substantiallyless than the diameter of the tube 36c. Further, the duct includes a topwall 42, that is predominately horizontal in a rearward direction andinitially curves upwardly and subsequently downwardly, walls 42-44 beingjoined together to form an opening of substantially the same size andshape as opening 23 to receive material discharged through opening 23.Joined to the rear edge of the top wall 42 to extend upwardly therefromis a wall 47, the wall 47 being located longitudinally rearwardly of theupper transverse edge of wall 44. A bottom wall 49 has its front edgejoined to the upper edge of the wall 44 and is downwardly and rearwardlyinclined along portion 49a, then extends downwardly and rearwardly alongsection 49b, and thereafter has a generally vertical portion 49c. Theduct also includes a rearwardly and downwardly inclined top wall 50 inoverlying relationship to the rearward part of wall portion 49a and thefront part of section 49b.

The upper front transverse edge of wall 50 is a substantial distancerearwardly of wall 47 whereby walls 50, 47 in connection with theadjacent parts of the side walls 43 form a suction port 52. The frontedge of wall 50 is located closely adjacent the plane of wall 44.

In order to selectively close the suction port to prevent movement offluid or other material therethrough, there is provided a door 54 havingan upper edge hingedly connected at 55 to the front portion of wall 50so that the door, in its open, depending position, is located asubstantial distance rearwardly of the junction of walls 44, 49, and hasits lower terminal edge a substantial distance above the verticallyadjacent part of wall 49. An arm 56 has one end pivotally connected at57 to the mid-portion of the door 54, an intermediate portion slidablyextended through a narrow slot in wall 50, and an opposite end pivotallyconnected at 58 to one end of an arm 59. The mid-portion of arm 59 ispivotally connected at 60 to bracket 61 that is mounted on the exteriorsurface of wall 50. The opposite end of arm 59 is connected through asuitable linkage (not shown) to be operated by an operator sitting onthe seat 31. The connections of the arms 56, 59 to one another and tothe door are loose to permit the door pivoting a limited amount in aclockwise direction as viewed in FIG. 2 to minimize damage to the doorwhen hit by heavy debris.

Located rearwardly of the duct D is a heavy trash receptacle, generallydesignated R, that in part is formed by the rearward portions of theside walls 43 of the duct D and wall portions 490, and the rearward partof wall portion 49b. Further, the heavy trash receptacle R includes atop wall 62 that has a front edge joined to the lower rear edge of wall50, a bottom framework 63 and a rear wall (not shown). Thus walls 50, 62adjacent the juncture thereof, wall portion 49b and the adjacent partsof the side walls form a throat that serves as an inlet to the trashreceptacle R. The framework 63 provides a plurality of dischargeopenings (not shown), each discharge opening being closed by a door 65that has a front end portion hingedly connected at 66 to the frameworkto permit the doors to be hingedly moved toward an open positionextending in a downard and forward direction. Other than for the inletthroat and the discharge openings, the receptacle is closed.

In order to move the doors between their open and closed positions, themid-portions of each of the transverse opposite edges of the doors hasthe lower end of an arm 67 pivotally connected thereto at 68, theopposite end of each arm being pivotally connected at 69 to a horizontalbar 70. To each bar 70 there is pivotally connected at 72, the one endsof parallel arms 71, the opposite ends of the parallel arms beingpivotally connected at 80 to the side walls 43. The front pivots 69 areslidably extended through elongated slots 74 in the control arms 73 toform a lost motion connection. The ends of the control arms opposite theslots 73 are pivotally connected at 76 to the side walls while themidportion of one of the arms is pivotally connected at 77 to a controlrod 78 that extends upwardly to adjacent the operator seat 31.

Through the above mentioned structure, the doors 65 may be pivoted fromtheir discharge opening closing position (solid line position of F IG.2) to a downwardly and rearwardly or even forwardly extending openingposition by moving the control rod 78 to pivot the control arms 73 in acounterclockwise direction about pivot 76 as viewed in FIG. 2. As thecontrol arms are pivoted in a counterclockwise direction, the horizontalbars 70 are forced rearwardly and at the same time pivot in acounterclockwise direction about the respective pivot 80 whereby thehorizontal arms 70 moves to a lower elevation. As the arms 70 move toprogressively lower elevations, the doors are pivoted downwardly andforwardly and may be pivoted to positions that the doors extenddownwardly and forwardly from their respective pivot 66 as viewed inFIG. 2. Thus, the plurality of doors 65 are simultaneously movablebetween a closed position and an open position. Advantageously resilientgaskets are provided around the discharge openings of the receptacle Ror on the doors to form the fluid seals between the doors and the bottomwall 63.

A suction blower, generally designated B is mounted on the main frameand has an inlet 82 that opens into the suction port 52. A vacuum takeoff duct 83 opens to the inlet 82 and extends transversely outwardly topermit attachment of suitable devices to be operated by the vacuum. Aclosure (not shown) is provided for closing the duct 83. The suctionblower B has an outlet 84 that is fluidly connected to the forward endof the corrugated fluid conduit 85 which extends rearwardly to be influid communication with the inlet port 86 of the debris container C ofthe trailer unit 15 (See FIG. 4). The port 86 is provided in the frontwall 91 of the container C, a resilient gasket 88 being provided aroundthe port to form a matching fit with the discharge opening of the duct89 on which rearward end of the conduit 85 is mounted. The duct 89 ismounted at the upper end of a vertical standard 90, the lower end inturn being mounted on the main frame 16 of the trailer unit in astationary position. In this connection, the adjacent surfaces of duct89 and the front wall are sloped upwardly and forwardly to permit thecontainer C being moved to an emptying position without having todisconnect the duct 85 as will become more apparent hereinafter. Thefront wall 91 of the container C is provided with a vertically elongatedfront slot 91a in which the standard 90 extends when the container is inits datum position.

The container includes a lower, metal receptacle portion G and an upperfilter portion F, lower debris receptacle portion G having a bottom wall94. Dependingly secured to the rear comer portions of the bottom wallare transversely spaced brackets 95, longitudinally elongated arms 96each having one end pivotally connected at 97 to the brackets and anopposite end pivotally connected at 98 to the frame 16 forwardly of thewheels 17 but rearwardly of the container front wall 91. A second set ofarms 102 are pivotally connected to the brackets at locations that areforwardly and above pivots 97 when the container is in its solid linedatum position, the forward ends of the arms 102 being pivotallyconnected to the frame 16 at 104. The pivot axis of the pivots 104 is ata substantially higher elevation and forwardly of the pivots 98. Apiston cylinder combination has a piston rod 108 pivotally connected at109 to a transverse member 102a that has opposite ends secured to arms102 at a location that is longitudinally intermediate pivots 103 and104, and a cylinder 110 that is pivotally connected to the frame 16 at 11 1. Pivot member 11 1 is located below and generally transverselybetween pivot members 98. Due to the location of the pivotalconnections, the arms 96, 102 and the piston cylinder combinationrelative to each other and the frame and the container, as the pistonrod is moved toward its extended position, arms 102 are pivoted aboutpivot members 104 in the direction of the arrow 112 while arms 96 arepivoted in a corresponding direction about pivots 98. Since this resultsin pivot members 103 moving vertically upwardly at a slightly fasterrate than pivot members 97 are moved vertically upwardly, the brackets95 pivot about pivot members 103 in a direction of arrow 115 while saidbrackets pivot in a corresponding direction about pivot members 97. Thatis, as viewed in FIG. 4, as the arms are pivoted in a clockwisedirection about the pivot members connecting said arms to the frame, thecontainer pivots about pivot members 97, 103 in the counterclockwisedirection. Accordingly, since the arms in the container datum positionextend predominantly horizontally, the initial movement of the containeris predominantly vertical while upon the piston rod approaching itsextended condition, the container is pivoted in a counterclockwisedirection at progressively increasingly larger angular increments forthe same increments of progressively vertical movement of the pivot 97.As a result, upon container reaching the elevated dumping dotted lineposition of FIG. 4, the floor of the container is inclined at asubstantial angle downwardly and rearwardly with the rear end of thefloor being rearwardly of the frame 16 which terminates adjacent rearportion of the wheels 17.

In order to facilitate dumping the container, there is provided a door119 for removably closing the bottom discharge opening provided in therear wall 120 of the container receptacle. In order to mount the doorfor movement between its solid line closed position and its dotted lineopen position illustrated in FIG. 4, a bracket 122 is mounted within thereceptacle on the rear wall, a pivot member 123 mounted by the bracketpivotally mounting one end of the somewhat U-shaped arm 124. Anintermediate portion of the arm has a piston rod 125 pivotally connectedthereto at 127. The piston rod forms part of a piston cylindercombination 125, 126 that includes a two-way acting cylinder 126 and ispivotally attached to the bracket 122 at 128. In the door closedposition, the pivot 127 is located vertically and longitudinallyintermediate pivots 123, 128. The opposite end of the arm 124 is weldedto the upper rear portion of the door 119. Upon applying fluid underpressure to the upper end of cylinder 126, pivot 127 is swung through adownwardly extending arc while the door is swung through an arc in arearward and upward direction, the foregoing assuming the receptacle inits datum solid line position of FIG. 4. By the above describedstructure, the door can be retained in its closed position till thecontainer C has been moved to its dumping position, and then fluid underpressure applied to one end of the cylinder for moving the door relativethe receptacle to open the discharge outlet of the receptacle.Thereafter, fluid under pressure may be applied to the opposite end ofthe cylinder for moving the door to its closed position and retainingthe door in the closed position.

A generally rectangular frame 131 is attached to the upper peripheraledge of the receptacle for mounting the fabric filter 132 to extendthereabove and in fluid sealing relationship with the receptacle.Suitable support members (not shown) may be provided to prevent collapseof the fabric filter when air under pressure is not being dischargedinto the container. Other filters can be used, for example, an envelopefilter.

In order to prevent debris in the airstream from directly impinging onthe filter, to diffuse the air flow and to deflect the debris to spreadthroughout the receptacle so as not to bunch in one pile, there isprovided a deflector 175. Advantageously the deflector may be made froma single sheet of flexible material, for example, rubber, that hasvertical slits to form upper edge portions 175a that are secured to thecontainer front wall vertically above the container inlet port 86. Theremainder of the deflector depends from the upper edge portion to have alower terminal edge at a substantially lower elevation than the inletport, the deflector being of a substantially greater width than theinlet port. When air under pressure is discharged from duct 85, thedeflector lower end portion is forced further away from the containerinlet 86 to direct the airstream generally downwardly and transverselyoutwardly, the degree of flexibility and weight of the deflector beingsuch to prevent the deflector from bending to a position in which theairstream could flow directly rearwardly from the inlet port 86.

Referring now to FIG. 7, the drive and brake mechanism, generallydesignated 140 will now be set forth. The mechanism 140 includes ahydraulic motor 141 having a motor shaft 141a to which there is keyed ashaft 142, the shaft being rotatably mounted in the differential casing143. To the opposite end portion of the shaft 142 there is keyed a brakedisc 145 that extends within the confines of an axially movable brakehousing 147 The brake housing is mounted for axial movement byconventional mechanism 148 that includes mechanical and/or hydrauliclinkages to the brake pedal adjacent the operators seat for moving thebrake housing to brakingly engage the brake disc.

The intermediate portion of the shaft 142 is provided with teeth fordriving a larger diameter gear 150 that is rotatably mounted by thecasing 143, the gear in turn driving the gear 151 that is bolted to thedifferential 152 that drives the front axle 152a. The axle 152a in turnhas the drive unit wheels 13 mounted thereon for being driven by theaxle. With the aforementioned structure, the braking action is directlyapplied to the motor driven shaft, rather than to the wheel axle 152a,for increasing the braking efficiency.

The hydraulic motor 141 is a fluid driven, bidirectional, in line,variable piston motor with a two positioned swash plate lever controlfor selectively operating the motor to drive the shaft 142. For drivingmotor 141 and the suction blower, there is provided an engine 156 on thedrive unit frame that has a pulley 157 on the engine shaft for drivingthe V-belt 158. The V- belt drives the variable volume, over-center,in-line piston pump 159 which through suitable hydraulic circuitry 160drives the motor 141 at variable speeds and in either angular direction.

In using the apparatus of this invention for collecting deep or highaccumulations of bulky material, in the preferred type of operation theleaf seal flap 27 is moved to and retained in its elevated position bythe push-pull cable assembly 30 and the paddle wheel motor rotates thepaddle wheel in the direction of the arrow 200. At this time, as theunit moves forwardly into the pile of debris, the paddle wheel flaps 36dand the flexible tube 36c will start accelerating material to initiallywedge the material between the tube and the ground and thence push itaround and up the skirt 24 and into the airstream provided by operatingthe suc tion blower. The airstream is of a sufficiently high ve locityto convey most of the debris thrown upwardly into the housing H by thepaddle wheel to move said debris rearwardly of the upper edge of plate44, the general trajectory of the debris being indicated by the arrows201. The very light debris flows upwardly through port 52 with theairstream without contacting door 54. However the trajectory of theother material is such to strike door 54, the heavy thence fallingdownwardly to wal 49 and into the heavy trash receptacle while theremainder of the material striking the door is air conveyed through thesuction port 52. For example, large light objects such as popcorn boxesfrequently would be of sufficient weight not to be carried directly intoport 52, but rather would strike door 54, and thereafter would becarried by the airstream upwardly through port 52. This mode ofoperation especially lends itself to picking up large, bulky and lightmaterial. However, this mode of operation does not do as good a job ofpicking up heavier objects as when the flap 27 is in its solid lineposition of FIG. 2 and the paddle wheel is rotated in the directionopposite arrow 200.

When the leaf seal 27 is lowered to its solid line position of FIG. 2and the paddle wheel rotated in the direction opposite arrow 200, uponmoving the machine across surface having debris thereon, the objectsthat pass under the leaf seal 27 are engaged between the flaps of thepaddle wheel and are carried up the back side of the leaf seal betweenthe paddle wheel and the leaf seal and panel 21 to be thrown by thepaddle wheel into the airstream. The flexible tube 360 can engage largeobjects and carry them around the back side of the leaf seal andadjacent panel 21, and in part the throwing action of the paddle wheeltends to throw the objects upwardly between walls 42, 44 of the ducts,the trajectory of the material being generally along and adjacent thefront wall 20 indicated by arrows 202. As a result, this mode ofoperation is better for heavy objects than that described in thepreceding paragraph. lf sufficiently large debris items are encounteredon the surface so as to cause the leaf seal to bend backwardly into thepath of travel of the flaps 36 d of the paddle wheel, the panel 21 andleaf seal attached thereto will hinge about the axis of the clearinghinge 22 in a counterclockwise direction as viewed in FIG. 2 to move theleaf seal upwardly sufficiently to clear the leaf seal from engagementwith a large object. Thereupon the panel and leaf seal returns to thevertical position under the action of gravity. As a result the clearingof the leaf seal is automatic. To be noted is that the cable assemblypermits the flap 27 and panel 21 pivoting as a single unit. The rotationof the paddle wheel in the direction opposite arrow 200 and leaf seal inthe datum position of FIG. 2 is not only good for picking up lightdebris loads but also for picking up small dense items such as rocks,nuts, bolts and pop bottles.

The debris in moving upwardly through the housing and into the duct Dwill result in a separation of the heavier objects from the lighterparticles, the lighter particles being carried up to port 52 and intothe suction blower housing to be discharged from the outlet 84. Materialpassing through the outlet 84 passes through the conduit 85 and into thecontainer C. In the container, the debris laden airstream in passingbeneath deflector 17S and in expanding deposits the heavier debriscarried in the stream over the floor 94 while the lighter debris isretained in the container by filter F as the air passes outwardlythrough the filter. The heavier objects moving into the duct D eitherstrike the door 54 to fall downwardly onto the wall 49 and thence passinto the heavy debris receptacle R or pass between the door in its openposition and the bottom wall 49. As a result, a separation of theheavier and lighter materials takes place in the duct D.

Ribs 54a are provided on the door 54 (forward side of the door in anopen position) to permit air to flow behind objects such as paper andthereby discourage the large light articles such as paper or cardboardfrom becoming attached thereto. During the time the apparatus of thisinvention is being moved from one location that has been cleaned toanother location, the door 54 advantageously is closed and the lever 172pivoted for moving the housing to its elevated position. Also, it isadvantageous to close the door 54 during the dumping of debris from thecontainer C to prevent an airstream flowing into the container andblower material in the container into the area exterior of the containerwhen the container is dumped. Further, if it is desired to use thevacuum for another device that is connected to the duct 83, the door 54is advantageously moved to its closed position.

At the time it is desired to empty the receptacle R, the lever 78 isoperated to move the arms 70 and thereby the doors to their opencondition in the manner previously described.

It is to be understood that the container C may be mounted for dumpingby conventional mechanism in place of that described herein; and thatother mechanism may be used for mounting the door 119.

It is to be understood that wall 49 could be vertical and the receptacleR located further forwardly than that shown in FIG. 2 as long as themodified wall 49 was rearwardly of wall 44 and forwardly of door 54.Further it is to be understood that in place of door 54, the duct Dcould be provided with a generally vertical impact wall at the locationof door 54 in its open position. However door 54 is preferred as it maybe used to closed port 52 for reasons previously set forth.

Instead of making the paddle wheel with portions 36d axially across tube36c substantially parallel to a plane of the axis of rotation of thepaddle wheel, the flap portions may be a spiral configuration. However,flap portions that are substantially parallel to said plane arepreferred as they cut down the air losses.

For some cleaning opeations, a brush could be rotatably mounted inhousing H. A brush would be better for picking up debris such as sand,but would not be nearly as good as the paddle wheel of this inventionfor picking up debris such as leaves and paper.

Also, in place of the paddle wheel a rotary rake may be mounted in thehousing H. A rake would be better for picking up objects such as cans,pop bottles and paper in relatively tall grass than the paddle wheel ofthis invention. However, for cleaning areas such as parking lots, paddlewheel 36 is preferred.

With this invention, the heavy trash falls into the receptacle R. As aresult the heavy trash does not pass through the suction blower, andaccordingly there is less wearing of the blower impeller and blowerhousing. Further, as the heavy trash is not air conveyed to thecontainer C, a lower rate of air flow is required for picking up heavytrash than if both heavy and lighter trash were air conveyed tocontainer C. As a result, there is less air to be filtered and lesspower is required for driving the blower.

Since the trash in container C is generally of relative light nature,for example paper and leaves, after being dumped, it may be easilycompacted, the receptacle C being of a substantially larger capacitythan the receptacle R. The trash in receptacle R is generally of adense, heavy nature.

With this invention, the housing H is located forwardly of the axis ofrotation of the front wheels 13 while the heavy trash receptacle islocated rearwardly of said axis and the suction blower is located abovethe heavy trash receptacle. With the heavy trash receptacle beingbetween the trailer unit and the axis of rotation of the front wheels,part of the weight of the receptacle is supported by the rear wheels. Asa result, the power unit is of a shorter length and the front wheels ofa smaller size than if both the heavy trash receptacle and the pick upunit were located forwardly of the axis of rotation of said wheels.Additionally with the heavy trash receptacle being on the opposite sideof the axis of rotation of the front wheels from the pick up unit, agood balance and weight distribution, part on each side of the axis, isobtained, and the machine is more maneuverable than if both were locatedforwardly of said axis. The center of gravity of the container C in itsdatum position is located above the rear wheels. Additionally with thetrailer unit and a power unit being connected by an articulated joint,the vehicle is particularly suitable for use over relative roughterrain.

We claim:

1. A surface cleaning machine comprising a mobile vehicle having aframe, a downwardly opening debris pick up housing, said housing havinga debris outlet, first means for mounting said housing on the frame, apower driven surface cleaning tool rotatably mounted in the housingadjacent the surface to be cleaned for raising debris from the surface,a combination filter and light debris collection container, second meansfor mounting the container on the frame, a suction blower having adischarge outlet and an inlet, third means for fluidly connecting theblower outlet to the container, a

heavy trash receptacle mounted on the frame and having an inlet, andduct means for deflecting material passing therethrough to separateheavier material from lighter material, said duct means including a ductinlet fluidly connected to the housing outlet, a duct first outletfluidly connected to the blower inlet, a second duct outlet at a lowerelevation than the first duct outlet opening to the trash receptacleinlet, a bottom wall sloped upwardly and rearwardly of the housinginlet, a duct branch having the second duct outlet, 21 bottom wall and atop wall sloped downwardly and rearwardly from the first duct outlet,the first duct outlet being at a substantially higher elevation than thefirst mentioned bottom wall and extending rearwardly thereof, atransverse, vertically extending impact surface member adjacent the ductfirst outlet on the opposite side thereof from the duct inlet, extendingto at least substantially the same elevation as the duct first outlet,and having a lower edge at a higher elevation than the lowermost part ofthe trash receptable inlet, and means hingedly mounting the impactmember on the top wall to depend therefrom to permit pivoting of theimpact member for minimizing damage to the door when hit by heavydebris.

2. A surface cleaning machine normally driven in a forward direction,comprising a mobile vehicle having a frame, a downwardly opening debrispick up unit having a debris outlet, first means for mounting the uniton the frame, a combination filter-debris container mounted on theframe, and second means, including a suction blower, fluidly connectedto the unit outlet for drawing air and air entrained debris from theunit and discharging the air and entrained debris in the container, theunit including a housing having front, rear and side walls joinedtogether, a rear skirt dependingly mounted on the rear wall, side skirtsdependingly mounted on the side walls, a front panel having an upperedge portion hingedly connected to the front wall for movement between adepending position abutting against the side walls and a forwardlyextending position, a leaf flap, third means dependingly hingedlyconnecting the leaf flap to the front panel for movement between agenerally vertically extending position and a generally forwardlyextending position, control means mounted on the housing for selectivelyretaining the leaf seal in its generally horizontal extending position,and power driven rotary means mounted in the housing adjacent thesurface for moving material upwardly into the housing.

3. The apparatus of claim 2 further characterized in that the leaf flapin its generally vertical position includes a reversely bent,transversely extending first flap portion, and a generally verticalsecond flap portion abutting against the first flap portion on theforward side thereof and extending to a substantially lower elevationthan the first flap portion, said first and second flap portion havingtransversely spaced, vertical slits extending through the lower partsthereof.

4. A surface cleaning machine comprising a mobile vehicle having aframe, a downwardly opening debris pick up housing, said housing havinga debris outlet, first means for mounting said housing on the frame, apower driven surface cleaning tool rotatably mounted in the housingadjacent the surface to be cleaned for raising debris from the surface,a combination filter and a light debris collection container, secondmeans for mounting the container on the frame, a suction blower having adischarge outlet and an inlet, third means for fluidly connecting theblower outlet to the container, a heavy trash receptacle mounted on theframe and having an inlet, and duct means for deflecting materialpassing therethrough to separate heavier material from lighter material,said duct means including a duct having an inlet fluidly connected tothe housing outlet, a duct first outlet fluidly connected to the blowerinlet and a second duct outlet at a lower elevation than the first ductoutlet opening to the trash receptacle inlet, a bottom wall slopedupwardly and rearwardly of the housing inlet, and a duct branch havingthe second duct outlet, a bottom wall sloped downwardly and rearwardlyfrom the first mentioned bottom wall and a top wall sloped downwardlyand rearwardly from the first duct outlet, the first duct outlet beingat a substantially higher elevation than the first mentioned bottom walland extending rearwardly thereof, said tool comprising a paddle wheel,said housing including a front wall, a front panel having an upper edgeportion and a lower edge portion fourth means connecting the upper edgeportion to the front wall for mounting the panel for limited pivotalupward movement from a datum position, said fourth means comprisingfirst hinge means having a transverse hinge axis for mounting the frontpanel for movement, a flexible front flap, and fifth means fordependingly mounting the front flap on the panel lower edge portion toextend closely adjacent and normally forwardly of the path of angularmovement of the paddle wheel; said front flap being of sufficientflexibility to be bendable into said path of movement by relativelyheavy debris on the surface being cleaned as the machine movesforwardly, said fifth means comprising second hinge means having atransverse hinge axis for mounting the front flap for movement between adepending position and a generally horizontally extending position, andsixth means mounted on the housing for selectively retaining the frontflap in the generally horizontally extending position.

5. The apparatus of claim 4 further characterized in that the sixthmeans includes a mounting bracket mounted on the front panel and meansmounted by the bracket and connected to the front flap to permit a forcebeing transmitted from the paddle wheel to the front flap to pivot boththe front flap and front panel as a single unit about the front panelhinge axis.

6. A surface cleaning maching normally driven in a forward direction,comprising a mobile vehicle having a frame, a downwardly opening debrispick up unit having a debris outlet, first means for mounting said uniton the frame, a combination filter-debris container mounted on theframe, and second means fluidly connected to the unit outlet for drawingair and air entrained debris from the unit and discharging the air andentrained debris in the container, said unit including a housing havingsaid debris outlet, said housing including joined side, rear and frontwalls, a rear skirt mounted on the rear wall to extend downwardly andforwardly thereof, side skirts mounted on the side walls, and leaf sealmeans mounted on the front wall, the leaf seal means including a frontpanel, third means to hingedly connect the front panel to the front wallfor movement between a predominantly downwardly extending datum positionand a substantially more forwardly extending position, a resilient leafflap, fourth means for dependingly hingedly mounting the leaf flap onthe front panel for movement between a generally downwardly dependingposition and a generally forwardly extending position, and fifth meansmounted on the housing for selectively retaining the leaf flap in itsgenerally forwardly extending position, said front wall being inclinedupwardly and rearwardly, the rear wall having an upper wall portioninclined at about the same angle as the front wall, said first meansincluding a duct having an inlet branch in fluid communication with theunit outlet, said inlet branch having a bottom wall in substantially thesame plane as the housing rear wall portion, an airstream outlet porthaving a rear edge located substantially rearwardly and above the inletbranch bottom wall and closely adjacent the plane of the inlet branchbottom wall, and a heavy trash outlet branch having a bottom wallextending downwardly of the outlet port, a heavy trash receptacleopening to the heavy trash branch, a paddle wheel made of resilientmaterial and having diametrically opposed flap portions that in ahorizontal position have outer edges spaced slightly less than thecorresponding horizontal spacing of the rear wall and the leaf sealmean, and means including a shaft mounted in the housing for mountingthe paddle wheel adjacent the surface to be cleaned and drivinglyrotating the paddle wheel, and power means drivingly connected to theshaft for rotating the shaft, the second means including a suctionblowerhaving an inlet fluidly connected to the outlet port, a door forclosing the blower inlet and means for mounting the door to hingedlydepend adjacent the outlet port rear edge and said door beingselectively movable to close said blower inlet.

7. The apparatus of claim 6 further characterized in that the leaf flaphas a lower portion bendable into the path of rotary movement of thepaddle wheel, the fourth means hingedly connecting the flap to the frontpanel to move the front panel and leaf flap as a single unit about thethird means hinge axis in a direction away from the paddle wheel whenthe paddle wheel engages the lower portion and is rotating in adirection that the lower part of the paddle wheel is rotating toward theflap.

8. The apparatus of claim 6 further characterized in that said powermeans is bi-directional for selectively rotating the shaft in eitherangular direction.

9. A surface cleaning machine comprising a mobile vehicle having aframe, a downwardly opening debris pick up housing, said housinghaving adebris outlet, first means for mounting said housing on the frame, apower driven surface cleaning tool rotatably mounted in the housingadjacent the surface to be cleaned for raising debris from the surface,a combination filter and light debris collection container, second meansfor mounting the container on the frame, a suction blower having adischarge outlet and an inlet, third means for fluidly connecting theblower outlet to the container, a heavy trash receptacle mounted on theframe and having an inlet, and duct means for deflecting materialpassing therethrough to separate heavier material from lighter material,said duct means including a duct inlet fluidly connected to the housingoutlet, a duct first outlet fluidly connected to the blower inlet, asecond duct outlet at a lower elevation than the first duct outletopening to the trash receptacle inlet, a bottom wall sloped upwardly andrearwardly of the housing inlet, a duct branch having the second ductoutlet, a bottom wall and a top wall sloped downwardly and rearwardlyfrom the first duct outlet, the first duct outlet being at asubstantially higher elevation than the first mentioned bottom wall andextending rearwardly thereof, a transverse, vertically extending impactsurface member adjacent the duct first outlet on the opposite sidethereof from the duct inlet, extending to at least substantially thesame elevation as the duct first outlet, and having a lower edge at ahigher elevation than the lowermost part of the trash receptacle inlet,means hingedly mounting the impact member on the top wall to dependtherefrom, said impact member comprising a door for closing the firstduct outlet to block the flow of debris therethrough, and means forselectively moving the door between a position depending relative thetop wall and a position closing the first duct outlet, the lastmentioned means being connected to the door to permit limited hingedmovement thereof when the door is in depending relationship to the topwall.

1. A surface cleaning machine comprising a mobile vehicle having aframe, a downwardly opening debris pick up housing, said housing havinga debris outlet, first means for mounting said housing on the frame, apower driven surface cleaning tool rotatably mounted in the housingadjacent the surface to be cleaned for raising debris from the surface,a combination filter and light debris collection container, second meansfor mounting the container on the frame, a suction blower having adischarge outlet and an inlet, third means for fluidly connecting theblower outlet to the container, a heavy trash receptacle mounted on theframe and having an inlet, and duct means for deflecting materialpassing therethrough to separate heavier material from lighter material,said duct means including a duct inlet fluidly connected to the housingoutlet, a duct first outlet fluidly connected to the blower inlet, asecond duct outlet at a lower elevation than the first duct outletopening to the trash receptacle inlet, a bottom wall sloped upwardly andrearwardly of the housing inlet, a duct branch having the second ductoutlet, a bottom wall and a top wall sloped downwardly and rearwardlyfrom the first duct outlet, the first duct outlet being at asubstantially higher elevation than the first mentioned bottom wall andextending rearwardly thereof, a transverse, vertically extending impactsurface member adjacent the duct first outlet on the opposite sidethereof from the duct inlet, extending to at least substantially thesame elevation as the duct first outlet, and having a lower edge at ahigher elevation than the lowermost part of the trash receptable inlet,and means hingedly mounting the impact member on the top wall to dependtherefrom to permit pivoting of the impact member for minimizing damageto the door when hit by heavy debris.
 2. A surface cleaning machinenormally driven in a forward direction, comprising a mobile vehiclehaving a frame, a downwardly opening debris pick up unit having a debrisoutlet, first means for mounting the unit on the frame, a combinationfilter-debris container mounted on the frame, and second means,including a suction blower, fluidly connected to the unit outlet fordrawing air and air entrained debris from the unit and discharging theair and entrained debris in the container, the unit including a housinghaving front, rear and side walls joined together, a rear skirtdependingly mounted on the rear wall, side skirts dependingly mounted onthe side walls, a front panel having an upper edge portion hingedlyconnected to the front wall for movement between a depending positionabutting against the side walls and a forwardly extending position, aleaf flap, third means dependingly hingedly connecting the leaf flap tothe front panel for movement between a generally vertically extendingposition and a generally forwardly extending position, control meansmounted on the housing for selectively retaining the leaf seal in itsgenerally horizontal extending position, and power driven rotary meansmounted in the housing adjacent the surface for moving material upwardlyinto the housing.
 3. The apparatus of claim 2 further characterized inthat the leaf flap in its generally vertical position includes areversely bent, transversely extending first flap portion, and agenerally vertical second flap portion abutting against the first flapportion on the forward side thereof and extending to a substantiallylower elevation than the first flap portion, said first and second flapportion having transversely spaced, vertical slits extending through thelower parts thereof.
 4. A surface cleaning machine comprising a mobilevehicle having a frame, a downwardly opening debris pick up housing,said housing having a debris outlet, first means for mounting saidhousing on the frame, a power driven surface cleaning tool rotatablymounted in the housing adjacent the surface to be cleaned for raisingdebris from the surface, a combination filter And a light debriscollection container, second means for mounting the container on theframe, a suction blower having a discharge outlet and an inlet, thirdmeans for fluidly connecting the blower outlet to the container, a heavytrash receptacle mounted on the frame and having an inlet, and ductmeans for deflecting material passing therethrough to separate heaviermaterial from lighter material, said duct means including a duct havingan inlet fluidly connected to the housing outlet, a duct first outletfluidly connected to the blower inlet and a second duct outlet at alower elevation than the first duct outlet opening to the trashreceptacle inlet, a bottom wall sloped upwardly and rearwardly of thehousing inlet, and a duct branch having the second duct outlet, a bottomwall sloped downwardly and rearwardly from the first mentioned bottomwall and a top wall sloped downwardly and rearwardly from the first ductoutlet, the first duct outlet being at a substantially higher elevationthan the first mentioned bottom wall and extending rearwardly thereof,said tool comprising a paddle wheel, said housing including a frontwall, a front panel having an upper edge portion and a lower edgeportion fourth means connecting the upper edge portion to the front wallfor mounting the panel for limited pivotal upward movement from a datumposition, said fourth means comprising first hinge means having atransverse hinge axis for mounting the front panel for movement, aflexible front flap, and fifth means for dependingly mounting the frontflap on the panel lower edge portion to extend closely adjacent andnormally forwardly of the path of angular movement of the paddle wheel;said front flap being of sufficient flexibility to be bendable into saidpath of movement by relatively heavy debris on the surface being cleanedas the machine moves forwardly, said fifth means comprising second hingemeans having a transverse hinge axis for mounting the front flap formovement between a depending position and a generally horizontallyextending position, and sixth means mounted on the housing forselectively retaining the front flap in the generally horizontallyextending position.
 5. The apparatus of claim 4 further characterized inthat the sixth means includes a mounting bracket mounted on the frontpanel and means mounted by the bracket and connected to the front flapto permit a force being transmitted from the paddle wheel to the frontflap to pivot both the front flap and front panel as a single unit aboutthe front panel hinge axis.
 6. A surface cleaning maching normallydriven in a forward direction, comprising a mobile vehicle having aframe, a downwardly opening debris pick up unit having a debris outlet,first means for mounting said unit on the frame, a combinationfilter-debris container mounted on the frame, and second means fluidlyconnected to the unit outlet for drawing air and air entrained debrisfrom the unit and discharging the air and entrained debris in thecontainer, said unit including a housing having said debris outlet, saidhousing including joined side, rear and front walls, a rear skirtmounted on the rear wall to extend downwardly and forwardly thereof,side skirts mounted on the side walls, and leaf seal means mounted onthe front wall, the leaf seal means including a front panel, third meansto hingedly connect the front panel to the front wall for movementbetween a predominantly downwardly extending datum position and asubstantially more forwardly extending position, a resilient leaf flap,fourth means for dependingly hingedly mounting the leaf flap on thefront panel for movement between a generally downwardly dependingposition and a generally forwardly extending position, and fifth meansmounted on the housing for selectively retaining the leaf flap in itsgenerally forwardly extending position, said front wall being inclinedupwardly and rearwardly, the rear wall having an upper wall portioninclined at about the same angle as the frOnt wall, said first meansincluding a duct having an inlet branch in fluid communication with theunit outlet, said inlet branch having a bottom wall in substantially thesame plane as the housing rear wall portion, an airstream outlet porthaving a rear edge located substantially rearwardly and above the inletbranch bottom wall and closely adjacent the plane of the inlet branchbottom wall, and a heavy trash outlet branch having a bottom wallextending downwardly of the outlet port, a heavy trash receptacleopening to the heavy trash branch, a paddle wheel made of resilientmaterial and having diametrically opposed flap portions that in ahorizontal position have outer edges spaced slightly less than thecorresponding horizontal spacing of the rear wall and the leaf sealmean, and means including a shaft mounted in the housing for mountingthe paddle wheel adjacent the surface to be cleaned and drivinglyrotating the paddle wheel, and power means drivingly connected to theshaft for rotating the shaft, the second means including a suctionblower having an inlet fluidly connected to the outlet port, a door forclosing the blower inlet and means for mounting the door to hingedlydepend adjacent the outlet port rear edge and said door beingselectively movable to close said blower inlet.
 7. The apparatus ofclaim 6 further characterized in that the leaf flap has a lower portionbendable into the path of rotary movement of the paddle wheel, thefourth means hingedly connecting the flap to the front panel to move thefront panel and leaf flap as a single unit about the third means hingeaxis in a direction away from the paddle wheel when the paddle wheelengages the lower portion and is rotating in a direction that the lowerpart of the paddle wheel is rotating toward the flap.
 8. The apparatusof claim 6 further characterized in that said power means isbi-directional for selectively rotating the shaft in either angulardirection.
 9. A surface cleaning machine comprising a mobile vehiclehaving a frame, a downwardly opening debris pick up housing, saidhousing having a debris outlet, first means for mounting said housing onthe frame, a power driven surface cleaning tool rotatably mounted in thehousing adjacent the surface to be cleaned for raising debris from thesurface, a combination filter and light debris collection container,second means for mounting the container on the frame, a suction blowerhaving a discharge outlet and an inlet, third means for fluidlyconnecting the blower outlet to the container, a heavy trash receptaclemounted on the frame and having an inlet, and duct means for deflectingmaterial passing therethrough to separate heavier material from lightermaterial, said duct means including a duct inlet fluidly connected tothe housing outlet, a duct first outlet fluidly connected to the blowerinlet, a second duct outlet at a lower elevation than the first ductoutlet opening to the trash receptacle inlet, a bottom wall slopedupwardly and rearwardly of the housing inlet, a duct branch having thesecond duct outlet, a bottom wall and a top wall sloped downwardly andrearwardly from the first duct outlet, the first duct outlet being at asubstantially higher elevation than the first mentioned bottom wall andextending rearwardly thereof, a transverse, vertically extending impactsurface member adjacent the duct first outlet on the opposite sidethereof from the duct inlet, extending to at least substantially thesame elevation as the duct first outlet, and having a lower edge at ahigher elevation than the lowermost part of the trash receptacle inlet,means hingedly mounting the impact member on the top wall to dependtherefrom, said impact member comprising a door for closing the firstduct outlet to block the flow of debris therethrough, and means forselectively moving the door between a position depending relative thetop wall and a position closing the first duct outlet, the lastmentioned means being connected to the door to permit limited hingedmovement thereof when the door is in depending relationship to the topwall.